The joint association of diet quality and sleep regularity with incident cardiovascular disease in the multi-ethnic study of atherosclerosis

Abstract

Background/Objectives: Diet quality and sleep regularity both influence cardiovascular disease (CVD) risk and may influence each other, but there is scarce evidence for their joint or interacting associations in relation to CVD. We assessed these associations in the Multi-Ethnic Study of Atherosclerosis (MESA). Methods: Participants free of CVD with valid diet and sleep measures in 2010-2013 were included and followed through 2020 for detection of incident CVD (188 events detected over 8.8 years among 1782 participants; 55% women). Sleep timing and duration regularity were assessed via the intra-individual SD of sleep onset time and duration across 5- to 7-day actigraphy. The Alternate Healthy Eating Index-2010 assessed diet quality. Sleep regularity and diet quality were dichotomized and cross-tabulated to estimate joint associations with CVD and to evaluate interaction via Cox proportional hazard models adjusting for potential confounders. Results: Participants with low diet quality and irregular sleep had higher CVD risk compared to those with high diet quality and regular sleep (adjusted HR [95% CI]: low diet quality + irregular sleep timing: 1.56 [1.03, 2.37]; low diet quality + irregular sleep duration: 1.70 [1.09, 2.67]). The joint associations were stronger than those for only one adverse behavior and similar to those for their combination. There was no evidence for additive or multiplicative interactions. Conclusions: Having irregular sleep and low diet quality confers the highest CVD risk compared to having neither or only one of these behaviors. These results underscore the importance of interventions targeting these unhealthy lifestyle behaviors, especially when they co-occur.